Personal information belonging to about 1.5 million patients who visited Singapore Health Services' specialist outpatient clinics over the past three years has been compromised in a data breach that is being described as the biggest of its kind in the country.

The attackers specifically and repeatedly looked for data on medication being used by Singapore Prime Minister Lee Hsien Loong, though their motivation for doing so was not immediately apparent.

"Perhaps they were hunting for some dark state secret, or at least something to embarrass me," Loong wrote on his Facebook page. "If so, they would have been disappointed. My medication data is not something I would ordinarily tell people about, but there is nothing alarming in it."

Singapore's Ministry of Health Friday said the breach stemmed from a "deliberate, targeted and well-planned cyberattack." In a statement, the Ministry pointedly noted the attack was not the work of criminal gangs or casual hackers - seemingly implying in the process that a nation-state actor was behind the incident.

The data that was taken included national registration identity card numbers, names, birthdates, addresses, gender, and race information on 1.5 million people who had visited SingHealth's clinics between May 2015 and July 4, 2018. Other data such as patient diagnosis information, doctor's notes, and test results remained untouched. However, information on medications that were dispensed to some 160,000 patients was also compromised in the incident.

The attack is familiar to countless others in recent years targeting the healthcare industry. Just this week, LabCorp, one of the largest healthcare diagnostics firms in the US disclosed in an SEC filing that it had to take several systems offline - disrupting test processing and customer access as a result - after discovering suspicious activity on its network. Privacy Rights Clearinghouse, which maintains a database of publicly disclosed breaches, counts 167 breaches so far this year involving healthcare, medical providers, and health insurers. A lot of the activity is being fueled by the high value of medical data in the criminal underground.

In the Singapore incident, the apparent fact that the attackers specifically targeted data belonging to the nation's prime minister is concerning, says Itzik Kotler, CTO and co-founder of SafeBreach. "The healthcare vertical in particular is very interesting to attackers because their networks are often a key part of the national critical infrastructure, as in the case of SingHealth," he says. "The fact that the attackers targeted the Singapore PM’s personal information and outpatient medicine information is a concern," he notes. In the hands of the wrong people such data could potentially be used literally to trigger a life or death situation, Kotler says.

Unlike many data breach disclosure notices, the Singapore Ministry of Health's disclosure offered at least some details of the incident based on investigations by the Cyber Security Agency of Singapore (CSA) and the country's Integrated Health Information System.

According to the statement, database admins at SingHealth first spotted unusual activity on their network on July 4 and acted immediately to end it. A subsequent investigation showed that attackers had broken into the network and exfiltrated data between June 27, 2018 and July 4, 2018. The attackers had apparently accessed the SingHealth system by breaching a front-end workstation and using that foothold to obtain credentials for gaining privileged access to the backend database.

Following the incident, IT and security administrators at SingHealth have implemented several measures to shore up security, including additional controls on workstations and servers and resetting user and system accounts. Officials have also temporarily implemented "Internet surfing separation" as a precautionary measure, the SingHealth statement said.

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Jai Vijayan is a seasoned technology reporter with over 20 years of experience in IT trade journalism. He was most recently a Senior Editor at Computerworld, where he covered information security and data privacy issues for the publication. Over the course of his 20-year ... View Full Bio

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